The present invention relates to a steering system of an outboard motor including a steering handle for steering the outboard motor.
Some types outboard motors are provided with steering systems or apparatus each of which is manually operated by using a bar-like steering handle.
FIG. 7 is a plan view showing a conventional steering system of the above type, and with reference to FIG. 7, a steering bracket 92 is fixed to a front portion, i.e. hull side, of an outboard motor body (e.g. engine holder in FIG. 7) 91, a steering unit 93 is fixed to a front portion of the steering bracket 92 and a steering handle 94 extends forwardly from the side face of the steering unit 93 of the outboard motor. An engine is mounted on an upper portion of the engine holder and the like to which the steering bracket 92 is connected.
The steering bracket 92 is fixed to an upper end of a steering shaft 95 so as to be rotated together. The steering shaft 95 is rotatably supported by a clamp bracket (swivel bracket, not shown) which is fixed to a hull. If the steering handle 94 is turned to left or right, the outboard motor body 91 is turned around the steering shaft 95 and the hull is steered.
Conventionally, the steering bracket 92 is formed substantially symmetrically in a lateral direction with respect to a center line C of the outboard motor body 91. In such steering system, a steering unit 93 is omitted, and the steering handle 94 extends directly from a side of the steering bracket 92.
If parts, including such as oil filter, which are detachably attached to the engine of the outboard motor, are provided on a front surface of the engine, these parts are easy for a passenger to access and easy to be attached and detached, and this design facilitates maintenance. Especially, in the case of the oil filter, it is necessary to dispose the oil filter in the vicinity of an oil pump which is disposed in a lower portion of the engine, and it is ideal to dispose the oil filter on the front surface side of the lower portion of the engine.
However, in the conventional steering system, the steering bracket 92 is formed substantially symmetrically in the lateral direction with respect to the center line C of the outboard motor body 91 as described above. Therefore, even if an attempt is made to dispose the oil filter, for example, on the front surface of the lower portion of the engine which is mounted directly above the engine holder to which the steering bracket 92 is connected, it is difficult to dispose the oil filter or like due to the existence of the steering bracket 92, and even if such part or equipment could be disposed in such a position, it is difficult to access, and therefore, the maintenance performance (attaching and detaching operability) will be deteriorated.
Furthermore, some types of the outboard motors are provided with shifting (shift) device for interrupting the rotating force from the drive shaft to the propeller shaft or changing the rotational direction.
Such shift device is controlled remotely by a shift lever, which is usually arranged as a part of a remote-control unit at a portion near a steering seat in a large-sized ship or like, and on the other hand, in a small-sized ship or like, the shift lever is usually secured to a steering handle or steering bracket to which the steering handle is mounted. These members are integrally provided for the outboard motor, as disclosed, for example, in Japanese Patent Laid-open Publication No. HEI 6-144375 or No. HEI 10-218088), in each of which the shift device is operated through link means such as shift rod or shift cable extending from the shift lever.
In such conventional structure, however, in which the shift lever is secured to the sheering handle or steering bracket, no means is adopted for protecting the link means against force or impact from a horizontal side, for example.
Further, when the link means such as shift lever, shift rod or shift cable is broken, bent or cut, it is difficult to expect a suitable or steady clutching operation.
It is a primary object of the present invention is to substantially eliminate defects or drawbacks encountered in the prior art mentioned above and to provide a steering system arranged so as to make it possible to dispose an oil filter or like on a front surface of a lower portion of an engine in a state of an outboard motor mounted to a hull so as to facilitate the attaching and detaching operation of the oil filter or like.
It is another object of the present invention to provide a steering system of an outboard motor capable of protecting the oil filter or like disposed on the front surface of the lower portion of the engine against damage.
It is a further object of the present invention is to provide a steering system of an outboard motor provided with an improved steering handle and other operating members on a steering bracket.
It is a still further object of the present invention to provide a steering system of an outboard motor to facilitate maintenance of the steering handle and associated members or portions thereof.
It is a still further object of the present invention is to provide a steering system provided with a handle structure capable of protecting a shift lever and link means against impact or damage.
These and other objects can be achieved according to the present invention by providing, in one aspect, a steering system mounted to a body of an outboard motor comprising:
a steering bracket mounted, at one side thereof, to the body of the outboard motor which is mounted to a hull;
a steering shaft to which the steering bracket is mounted to be rotatable; and
a steering handle secured to another one side of the steering bracket,
the steering bracket being provided with a front overhang portion which extends forward from the steering shaft and supports the steering handle, the front overhang portion being arranged to be offset sideways from a center line of the body of the outboard motor as viewed in a plan view.
In a preferred embodiment of this aspect, the steering bracket is arranged such that the steering handle is disposed to be offset on an opposite side from the front overhang portion with respect to the center line.
The front overhang portion is provided, at a front end thereof, with a yoke extending in a widthwise direction of the body of the outboard motor, the front overhang portion and the yoke are arranged so as to provide a substantially T-shape as viewed on a plane, and the steering handle is provided on one side of the yoke. A shift lever is provided on another side of the yoke, and the yoke is detachably mounted to the front overhang portion. The yoke is mounted, at one end thereof, with a steering holder to which the steering handle is attached to be rotatable.
The steering bracket is provided with a pair of rear overhang portions extending rearward from the steering shaft.
According to this aspect of the present invention, since the front overhang portion of the steering bracket, on which the steering handle is supported is offset sideways with respect to the center line of the outboard motor body as viewed on a plane, a member or part such as the oil filter can be disposed on the front surface of the lower portion of the engine, and the attaching and detaching operation thereof can be facilitated.
Furthermore, in the steering system of the outboard motor of the present invention, since the steering bracket is formed such that the steering handle is offset towards the opposite side from the front overhang portion with respect to the center line of the outboard motor body as viewed in the longitudinal direction, the parts disposed on the front surface of the lower portion of the engine can be guarded and protected against damage.
Still furthermore, the front overhang portion is provided at its front end with the yoke extending in the widthwise direction of the outboard motor, and the front overhang portion and the yoke provide a substantially T-shape as viewed on a plane, the steering handle is provided on one side of the yoke, and the other operating member such as shift means is provided on the other side thereof. Therefore, it is possible to dispose the steering handle and the other operating member on the steering bracket efficiently.
Furthermore, since the yoke is detachably mounted to the front overhang portion, it is possible to facilitate maintenance of the steering handle and surrounding portions thereof.
The objects of the present invention can be also achieved by providing, in another aspect, a steering system mounted to a body of an outboard motor comprising:
a steering bracket mounted at one side thereof to the body of the outboard motor which is mounted to a hull;
a steering shaft to which the steering bracket is mounted to be rotatable;
a steering handle secured to another one side of the steering bracket;
a shift device adapted to control a rotational motion of a propeller means of the outboard motor; and
a shift lever operatively connected to the shift device through a link means,
the steering bracket being provided with a frame member in which the shift lever and the link means are accommodated.
In a preferred embodiment of this aspect, the shift lever is provided with a rotation shaft which is disposed to an inner upper portion of the frame member and the shift lever is provided with a connection portion for the link means, the connection portion being arranged inside the frame member. The rotation shaft comprises a fastening bolt having a head portion, the shift lever is formed with a recessed portion in which the head portion is accommodated and the shift lever is mounted to the frame member to be rotatable in a state that the head portion of the fastening bolt is accommodated in the recessed portion.
The link means includes a shift rod and shift cable connecting the shift lever and the shift device.
According to this aspect, since the shift lever for operating the shift device is disposed inside the frame member widened horizontally on the side portion of the steering bracket, an impact applied to the shift lever, for example, from the horizontal direction can be protected by the frame member. The connection portion formed to the shift lever for the link means is disposed inside the frame member, a horizontal impact applied to the shift rod can be also protected by the frame member.
Furthermore, since the shift lever is formed with the recessed portion which has a size allowing the head portion of the fastening bolt to be accommodated and the shift lever is mounted to the frame member to be rotatable, a horizontal impact applied to the head portion of the fastening bolt can be protected by the shift lever.
The nature and further characteristic features of the present invention will be made clear from the following descriptions made with reference to the accompanying drawings.